MikeOS 1.0 has been released. It is an open source PC operating system, designed as a tutor for basic OS design and x86 assembly language. "MikeOS is a 16-bit operating system for x86 PCs, written in assembly language, which boots from a floppy disk or CD-ROM. It features a text-based dialog-driven user interface, a command-line, support for FAT12 (DOS) floppies and PC speaker sound. It can load external programs and has over 30 system calls. Basic DOS .COM program support is also included." This version includes a complete Handbook with a whole section on writing your own OS.